229results about "Lead sulfides" patented technology

A nanostructured composite material comprising semiconductor nanocrystals in a crystalline semiconductor matrix. Suitable nanocrystals include silicon, germanium, and silicon-germanium alloys, and lead salts such as PbS, PbSe, and PbTe. Suitable crystalline semiconductor matrix materials include Si and silicon-germanium alloys. A process for making the nanostructured composite materials. Devices comprising nanostructured composite materials.

The present invention is directed to a process for synthesizing nanoparticles. This process involves providing a stable emulsion containing a plurality of droplets suspended in a continuous phase. The droplets, which are encapsulated by an interfacially-active material, contain a first reactant dissolved in a dispersed phase. The process also involves contacting a gas phase containing a second reactant diluted in a carrier gas with the stable emulsion under conditions effective to permit the first reactant and second reactant to react and form nanoparticles. The present invention further relates to nanoparticle-loaded emulsions and their uses in formulations for various purposes.

A method for synthesis of high quality colloidal nanoparticles using comprises a high heating rate process. Irradiation of single mode, high power, microwave is a particularly well suited technique to realize high quality semiconductor nanoparticles. The use of microwave radiation effectively automates the synthesis, and more importantly, permits the use of a continuous flow microwave reactor for commercial preparation of the high quality colloidal nanoparticles.

A high temperature (on the order of about 90° C. or above) non-aqueous synthetic procedure for the preparation of substantially monodisperse IV-VI semiconductor nanoparticles (quantum dots) is provided. The procedure includes first introducing a first precursor selected from the group consisting of a molecular precursor of a Group IV element and a molecular precursor of a Group VI element into a reaction vessel that comprises at least an organic solvent to form a mixture. Next, the mixture is heated to a temperature of about 90° C. or above and thereafter a second precursor which is different from the first precursor and is selected from the group consisting of a molecular precursor of a Group IV element and a molecular precursor of a Group VI element is added into the heated mixture. The reaction mixture is then mixed to initiate nucleation of IV-VI nanocrystals and the temperature of the reaction mixture is controlled to provide substantially monodispersed IV-VI nanoparticles having a diameter of about 20 nm or less.

A continuous flow reactor for the efficient synthesis of nanoparticles with a high degree of crystallinity, uniform particle size, and homogenous stoichiometry throughout the crystal is described. Disclosed embodiments include a flow reactor with an energy source for rapid nucleation of the procurors following by a separate heating source for growing the nucleates. Segmented flow may be provided to facilitate mixing and uniform energy absorption of the precursors, and post production quality testing in communication with a control system allow automatic real-time adjustment of the production parameters. The nucleation energy source can be monomodal, multimodal, or multivariable frequency microwave energy and tuned to allow different precursors to nucleate at substantially the same time thereby resulting in a substantially homogenous nanoparticle. A shell application system may also be provided to allow one or more shell layers to be formed onto each nanoparticle.

Provided are methods for producing nanostructures and nanostructures obtained thereby. The methods include heating a certain point of a substrate dipped into a precursor solution of the nanostructures so that the nanostructures are grown in a liquid phase environment without evaporation of the precursor solution. The methods show excellent cost-effectiveness because of the lack of a need for precursor evaporation at high temperature. In addition, unlike the vapor-liquid-solid (VLS) process performed in a vapor phase, the method includes growing nanostructures in a liquid phase environment, and thus provides excellent safety and eco-friendly characteristics as well as cost-effectiveness. Further, the method includes locally heating a substrate dipped into a precursor solution merely at a point where the nanostructures are to be grown, so that the nanostructures are grown directly at a desired point of the substrate. Therefore, it is possible to grow and produce nanostructures directly in a device. As a result, unlike the conventional process, it is not necessary to assemble and integrate the nanostructures produced in a sacrificial substrate into a device.

The invention discloses a steel wire rope picking waste acid and high zinc and lead-containing sludge co-disposal system and process and belongs to the technical fields of environmental protection and wastewater treatment. The steel wire rope picking waste acid and high zinc and lead-containing sludge co-disposal system disclosed by the invention comprises a mud acid stirring and dissolving device, a lead and zinc removal device, a flocculating agent preparation device, a hydrogen sulfide absorption device and a lead and zinc precipitation separation device, wherein the mud acid stirring and dissolving device is connected with the lead and zinc removal device through a pipeline; and the lead and zinc removal device is connected with the flocculating agent preparation device, the hydrogen sulfide absorption device and the lead and zinc precipitation separation device through pipelines. The steel wire rope picking waste acid and high zinc and lead-containing sludge co-disposal process disclosed by the invention comprises the following steps: stirring and dissolving mud acids, removing lead and zinc, preparing polyferric flocculants, purifying hydrogen sulfide tail gas and performing lead and zinc precipitation separation. According to the invention, steel wire rope picking waste acid and high zinc and lead-containing sludge co-disposal can be realized, the elements such as zinc and lead can be effectively removed, and industrial products with high additive values are prepared.

Monodisperse nanoparticles are prepared with a high degree of reproducibility by controlling pH in size-selective photoetching. The nanoparticles have uniform optical properties and other properties.

The invention discloses an ultra-small metal chalcogenide compound nano crystal and a biological synthesis method and application thereof. In one embodiment, the synthesis method is as follows: a protein with the isoelectric point PI lower than 9.0 and a metal salt are mixed with water evenly to form a mixed solution, the mixed solution is adjusted to alkaline, a reducing agent and a sulfur source are added for reaction to form the ultra-small metal chalcogenide compound nano crystal with the particle size less than 10nm. The method has the characteristics of mild reaction conditions, simple operation, direct use of particles without additional surface modification in biological photothermal therapy, and the like, the prepared ultra-small metal chalcogenide compound nano crystal is uniform in size, good in dispersion and high in stability, and the prepared ultra-small metal chalcogenide compound nano crystal has very good bio-compatibility without any surface modification, also has the photothermal effect, and is a great-application-prospect nano material used for photothermal therapy and biological fluorescence imaging.

A process for synthesizing nanostructures is disclosed. The process involves forming a liquid crystalline template by combining a block copolymer, a first reactant in a polar phase, and a nonpolar phase, then contacting the template with a gas phase composed of a second reactant, under conditions effective to form nanostructures.

The invention discloses a method preparing hexagram PBS nanocrystal. The process is as follows: cetyltrimethylammonium bromide is added into deionized water, and stirred efficiently to dissolve completely in the water, and then the transparent solution is obtained; lead acetate and thiourea are added into the transparent solution, stirred uniformly, and then added to the hydrothermal reaction kettle; the solution which is in the hydrothermal reaction autoclave keeps the temperature in 80 DEG C to 160 DEG C about 6 to 24 hours; the reaction autoclave is opened until the temperature is reduced to the room temperature through the natural cooling; and the solution is washed by deionized water and absolute ethyl alcohol, centrifugally filtrated; the precipitate is dried, and then the final product is obtained. The invention has the advantages of easy preparation, low reaction temperature, less energy consumption and low cost. The invention is beneficial to industrial production.

The invention relates to the method of the low temperature sulfuration translating the bad choosing complex oxidation lead zinc mine. The difficult choosing complex lead and zinc mine oxide, the sulfur, the fool's gold and the natrium sulfuration are served for the reagent sulfuration, the joining quantity of the sulfureted reagent is 0.5-10 percentage of the quantity of the difficult choosing complex lead and zinc mine oxide calculating by the element sulfur, the char repeat cover reagent such as the coke, the coke powder, the coal powder and the lead powder are mixing, the inert gases such as the argon gas and the azote gas are severed as the gas medium to add in the heating stove, the temperature keeps 100-900, the inert gas press keeps 0.01-0.1MPa, the lead and the zinc mine oxide is transferred to the sulfureted reagent after 10-180 minutes. On the said circumstance, the added sulfureted reagent can choose the lead, the zinc or the tantalum with the value to act, the single sulfureted reagent is gained, the other gangue factors can hold in the mine slurry without the change. The invention has many merits such as the easy process, the high percentage of reclaim of the metal, separating the lead and the zinc easy, the low wastage of the medicament, the realization of treating the metal with the value in advance.

The invention relates to a supergravity hydrothermal preparation method of spherical inorganic powder grains, which comprises the following steps: preparing a metal salt solution at a concentration of 0.001 to 2mol/L; adding a S<2-> chemical reagent into the obtained solution, and adjusting the pH value of the solution to dissolve the S<2-> chemical reagent, wherein the molar ratio of the metal salt ions to the sulfur ions is 1:1 to 1:5; adding an organic solvent or aqueous high polymer compound into the obtained solution, wherein the volume ratio of the organic solvent or aqueous high polymer compound to the metal salt solution is 1:1 to 1:50; pouring the mixed solution into a high-pressure reaction kettle, sealing the high-pressure reaction kettle, fixing the high-pressure reaction kettle on a fixed bracket in a hearth, and performing a hydrothermal reaction in the presence of supergravity at 50 to 250 DEG C for 0.1 to 5 hours under the action of a relative centrifugal force of 100 to 10,000 grams; and filtering the reaction product, washing the reaction product, and drying the reaction product under vacuum to obtain the needed product. The spherical inorganic powder grains prepared by the invention have the characteristics of high roundness, monodispersion and narrow distribution. The inorganic powder prepared by the method of the invention comprises ZnS, CdS, CuS, PbS, and the like. The inorganic powder grains can be used for manufacturing photonic crystals, rare earth luminescent materials, phononic crystals, solar materials, left-handed materials and the like.

The invention discloses a method for synthesizing a lead sulfide (PbS) film through the chemical in-situ reaction of a solution. The method comprises the steps of: (1) preparing a precursor solution; (2) preparing the PbS film through carrying out an in-situ reaction: vertically immerging a deposition substrate, of which a lead precursor film is attached to the surface, into a sulfur source anionic precursor solution for carrying out an in-situ chemical reaction, after 10 seconds, pulling the deposition substrate out of the reaction solution at a uniform speed, washing the deposition substrate by using deionized water, then, placing the deposition substrate in a drying box so as to form a PbS reaction deposition layer; and (3) carrying out heat treatment. The invention provides a novel in-situ chemical synthesizing method for the PbS film with high efficiency, convenience, little pollution and low cost, low-toxicity chemical raw materials, such as inorganic salt which serves as a precursor, alcohol ether and alcohol amine which serve as solvents, and the like, are adopted, and the PbS film is synthesized at a lower temperature, so that method for synthesizing the PbS film through the chemical in-situ reaction of the solution has the advantages of good evenness in solution deposition reaction, high degree of crystallizing, and easiness for controlling the thickness of the film.

The invention provides a preparation method of a porous PbS nano sheet and a porous PbS nano material prepared by the same. The preparation method comprises the steps of reacting inorganic lead salt with an organic molecule to obtain an organic lead source; and reacting the organic lead source with a Na2S solution to obtain the porous PbS nano material, wherein the mol ratio of the inorganic lead salt to the organic molecule is 1:0.5-6; the inorganic lead salt is selected from lead perchlorate, lead chloride, lead nitrate and mixture thereof, preferably the lead perchlorate; the organic molecule is a hydrosulfuryl molecule which is selected from thioglycollic acid, mercaptopropanoic acid, 1,2-dicarboxyl-1-ethanethiol, 1-hydrosulfuryl-2-sodium sulfonate ethane and mixture thereof, preferably the thioglycollic acid or the mercaptopropanoic acid; and the mercaptopropanoic acid is 3-mercaptopropanoic acid or 2-mercaptopropanoic acid. The method has simple steps and easy operation and can effectively control the topography of the porous PbS nano material. The porous PbS nano material obtained by the method has excellent visible light degradation performance.

The invention relates to a method for preparing water glass by utilizing waste lead-containing glass and separating a lead-containing compound. The method comprises the following steps of: firstly, making the lead-containing glass of an abandoned cathode-ray tube (CRT) into water glass fusion cake, hydrolyzing the fusion cake, and separating hydrolysate to obtain a water glass solution; then adding an additive to convert lead dissolved in the water glass into lead sulphide, separating and collecting lead sulphide sediment to obtain a lead-free potassium or sodium water glass solution, further treating dissolved residue to convert the lead-containing compound in the residue into lead sulphide, and recycling lead sulphide in the hydrolysis residue by adopting a floatation method. The method disclosed by the invention has the advantages that silicon, potassium and sodium ingredients in the lead-containing glass of the abandoned CRT can be converted into the water glass, recycling of the lead-containing compound is solved; the water glass is a basic inorganic chemical industry product with wide application range; and recycling of the lead-containing compound is solved, the recycled lead-containing compound can be taken as a raw material for lead smelting, and recycling of lead resource is realized.

A method for producing highly monodisperse nanocrystals comprising the steps of: a) preparing a precursor comprising a metal ion and a coordinating ligand; b) dissolving the precursor in a solvent mixture comprising coordinating solvent and optionally non-coordinating solvent; c) raising the temperature of the step b mixture into the range from 150° C. to 350° C.; d) adding a chalcogen to the step c heated mixture whereby the chalcogen reacts with the precursor; e) lowering the temperature of the step d mixture to stop the reaction; and e) maintaining the step e cooled mixture for sufficient time at sufficient temperature to narrow the size distribution of the nanocrystals. The methods greatly reduce or eliminate the need for trioctylphosphine oxide (TOPO); provide control over particle size, and permits facile production of high quality nanocrystals with very small diameters (<4 nm). CdSe nanocrystals produced via the methods are shown in the Figure.

The invention relates to a method for synchronously realizing water-phase transfer and nucleus targeting of hydrophobic nanoparticles, and belongs to the technical field of nanometer materials. The method comprises the general steps of adding a proper amount of organic solution with the hydrophobic nanoparticles to the aqueous solution containing a surface active agent with a certain concentration; stirring for an appropriate time; and then separating to remove residual surface active agent molecules, wherein the utilized surface active agent molecules contain quaternary ammonium salts at the hydrophobic ends. According to the method, such a surface active agent is adopted and used for modifying the hydrophobic nanoparticles, thus the water-phase transfer of the hydrophobic nanoparticles can be realized, and the nanoparticles show remarkable effect of nucleus targeting without requiring any additional modifications or treatments after the water-phase transfer.

The invention provides a preparation method of a thermoelectric compound. The preparation method comprises the following steps: (1) preparing raw materials; (2) ball-milling the raw materials through a dry method; (3) ball-milling the raw materials through a wet method; (4) drying; (5) pressing; and (6) sintering. The preparation method has the advantages of low cost, short preparation period, simple technology, energy saving, reduction on energy consumption, and suitability for massive industrial production, and is suitable for preparation of thermoelectric compounds such as PbS, SnS, and the like. The thermoelectric compounds prepared by the preparation method have the advantages of high compactness, low resistivity, low heat conductivity, and high thermoelectric performance.